Cash in old coin is English (7)

I believe the answer is:

realise

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'cash in' is the definition.
(I've seen this before)

'old coin is english' is the wordplay.
'old coin' becomes 'real' (real is a kind of coin. I am not sure about the 'old' bit.).
'english' becomes 'e' (abbreviation).
'real'+'is'+'e'='REALISE'

Can you help me to learn more?

(Other definitions for realise that I've seen before include "Become aware of; fulfil (S, not Z)" , "appreciate" , "Become fully aware of" , "work out" , "Ale, sire (anag.)" .)

I've seen this clue in The Telegraph.

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